I'm playing around with a Solr-powered search for my webapp, and I figured it'd be best to use the DataImportHandler to handle syncing with the app via the database. I like the elegance of just checking the last_updated_date
field. Good stuff. However, I don't know how to handle deleting documents with this approach. The way I see it, I've got 2 choices. I could either send an explicit message to Solr from the client when a document is deleted, or I could add a "deleted" flag and leave the object in the database, so that Solr will notice that the document has changed and is now "deleted." I could add a query filter that would disregard results with the deleted flag, but it seems inefficient to include all the deleted documents in the Lucene index. What do other folks do?
These are your options: